An ultrasonic diagnostic apparatus is often used for puncture. In this case, an operator watches a monitor display of an ultrasound image of a live body and a puncture needle, and insertion of the puncture needle. In the puncture operation, a puncture adapter is often used, and a puncture guide marker is displayed on the monitor to serve as a direction guide to assist an operator during needle insertion. In one puncture method, a puncture adaptor is fixed at a predetermined position of an ultrasonic probe body. In this method, an operator must read an angle value by watching a scale on the adaptor, and set the angle value for displaying the angle of the puncture marker of the ultrasonic diagnostic apparatus. This setting enables display of the puncture guide image with an ultrasonic image on the display monitor. In this technique, which entails operator's reading and setting, an operator perform angle reading and setting every time the operator changes an angle of the puncture needle. This is complicated for the operator.
In another method, the above mentioned angle of the puncture needle guide is detected by a sensor set by the puncture guide, and the detected angle is delivered to a processing unit in an ultrasonic diagnostic apparatus. (For example, see JP2004-305535A.) The sensor detecting the angle of the puncture needle guide is provided near a part moving in accordance with the changing angle of the puncture needle, (for example, see FIG. 6 or FIG. 7 in JP2004-305535A) and the sensor detects the angle indirectly or directly. In this method, the puncture marker image displayed on the monitor is automatically changed in accordance with the detected angle.
However the puncture adaptor is often removably constructed so that operator can mount and remove it from a standard ultrasonic probe. In this case, provision must be made for delivering detected signal to the apparatus body. For example, in the case that probe cables double as the connection to apparatus body, a connection structure such as a connecter connecting to the ultrasonic probe and a cable leaded from the puncture adaptor is necessary. On the other hand, in the case that another cable is connected to the apparatus body, the increasing number of cables adversely impact operability, and providing a new connecter for puncture is needed.
Because a guiding portion of the puncture adaptor guides a needle inserted into a body, body fluid and body tissues adhere to the guides. In this situation, the guiding portion must be easily disinfected and sterilized or must be disposable. However, in the above mentioned case, use of the sensor makes the structure complicated, makes disinfection or sterilization of the guide difficult, and makes the guide too expensive to be disposable.